Java高级应用之JNI

矫情吗；* 2022-04-06 08:44 261阅读 0赞

参考link  
\[url\]http://www.cnblogs.com/liuling/p/2013-12-20.html\[/url\]  
\[url\]http://blog.csdn.net/cl05300629/article/details/39050703\[/url\]  
  
1 创建Java包含native方法的类，如下：

public class TestNative
    {
       
    	public native void sayHello();
    }

2 通过JDK工具javah生成C/C++头文件，如下：

C:\Users\jacky_dai\Desktop\java>javah TestNative

3 生成如下的C++头文件，TestNative.h

/* DO NOT EDIT THIS FILE - it is machine generated */
    #include <jni.h>
    /* Header for class TestNative */
    
    #ifndef _Included_TestNative
    #define _Included_TestNative
    #ifdef __cplusplus
    extern "C" {
       
    #endif
    /*
     * Class:     TestNative
     * Method:    sayHello
     * Signature: ()V
     */
    JNIEXPORT void JNICALL Java_TestNative_sayHello
      (JNIEnv *, jobject);
    
    #ifdef __cplusplus
    }
    #endif
    #endif

4 创建C++ win32 DLL Project,并且包含java的include files并添加测试代码  
\[img\]https://img-blog.csdn.net/20140904123640781?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvY2wwNTMwMDYyOQ==/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast\[/img\]  
\[img\]https://img-blog.csdn.net/20140904123951644?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvY2wwNTMwMDYyOQ==/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast\[/img\]

#include <iostream>
    #include "TestNative.h"
    using namespace std;
    
    JNIEXPORT void JNICALL Java_TestNative_sayHello(JNIEnv *, jobject);
    {
       
        cout<<"hello world!"<<endl;
    }

5 添加Java测试代码

public class TestNative
    {
       
        public native void sayHello();
    
        /**
         * @param args
         */
        public static void main(String[] args) {
       
            System.loadLibrary("NativeCode");
            TestNative tNative = new TestNative();
            tNative.sayHello();    
        }
    }

6 编译运行demo，可以看见输出的“Hello World!”

javah TestNative.java
    java TestNative